The eruption of Mount Ontake has left 16 missing and 47 dead so far, but phone calls and other records indicate the numbers are likely to grow, Nagano prefectural officials said Friday.

After examining records assembled by police, firefighters and town officials, including missing persons reports and, in some cases, testimony from hikers who survived but have been unable to find their climbing companions, the true toll from the disaster is set to climb.

Police said earlier that 46 of the 47 victims were bludgeoned to death by falling rocks ejected by the eruption and the other victim died of burns, although no magma was observed.